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Is there such a thing as “hackerspace burnout” ?

Saturday, January 28th, 2012

After the awesome Chaos Communication Camp 2011, i had some difficulties to get involved with projects in the space for about a month and half: it’s like i lost something.

To put in context, i’ve been co-driving the truck that carried the material and luggage of 3 belgian hackerspaces and one dutch space up to Finowfurt and back. My co-driver did all the paperwork for the truck, made the whole pickup schedule, did the initial loading at the starting point, and even did the cooking every day since we arrived at the camp, while also taking care of his son. Hats off to that guy that will certainly recognize himself when reading this. On my side, i was busy coordinating the set up of our party tent (we barely had enough hands to raise it), doing all the wiring and light setup, and helping installing the tables and the network. The weather was not friendly either. After the camp was the teardown, packing and filling the truck, Then the driving back and final delivery to the different spaces, all on a very compressed schedule.

Now i feel the same thing again: i’ve been working in the space over the last month on a quite regular basis: drink shopping, moving shelves, filling fridge, garbage collection, rebuilding the electric installation nearly from scratch and dealing with the sharp aspects of socializing.

I want to work on my own pet projects and stop working on infrastructure and janitorial stuff for a while. For the ByteNight, i already made it clear that i will not get involved in any aspect of it. I’ll be there as a customer, sipping my drink on the sofa.

Once i finish the last missing bits on the electric installation, i will freeze all infrastructure projects (Zoppas, Parallel port interface, last power circuit and relay board) for some time.

Reboot in March 2012 ?

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Wall wart hunting

Tuesday, January 17th, 2012

I found in my apartment about 10 wall warts and two linear power supplies that give the same (or similar) voltage for my equipment.

Spools of red and black wire with a power supply

Let the hunt begin

I would like to get rid of those power bricks and have a more consistent and centralized setup. I hope to make some savings in the process by using a more efficient oversized switch mode power supply. Another advantage is that if i want an UPS on that line, i just need to connect a SLA battery.

My apartment will be wired with 6 mm² wires carrying 12VDC: one branch go to the networking area, the other two go to my desk.

Let’s lay down some wires !!

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1 minute hackjob: bicycle light battery

Sunday, October 30th, 2011

I needed a battery to power the front light of my bicycle last night, here is my solution. You will need:

  • A 4,5V flashlight battery
  • A zip tie
  • An adhesive pad for the zip tie
  • A nose pliers

  • Bend the battery terminals in two, crimp the hinge area.
  • Slightly lift the free side to facilitate the insertion of a wire
  • Attach the adhesive pad to the battery, slide the zip tie in the pad and attach the whole contraption to the bicycle
  • Insert the wires in the clamps you made earlier: let there be light. :-)
If you can’t find the adhesive zip tie pad, you can still use the good old fashioned duct tape. :-)

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Summer is over !!

Tuesday, October 18th, 2011

Three months of silence, but not of inactivity.

The CCC Camp was the big event in august, there are no words strong enough to describe the level of awesomeness i experienced during the camp. I needed a lot of time to prepare before and a lot of time after to bring things back to normal. It was really worth the energy i spent for that. Co-driving the truck was an interesting experience in itself. I have some video footage that still need editing.

Once i was back home, whenever there was sun shining, i wanted to be out: enjoying what’s left of it or cycling around.

With the summer now gone, i can work on the low season/winter projects:

  • Bicycle suitcase: The suitcase i carried on my bicycle got damaged after my fall in may, now i have no remorse gutting it. :-)
  • RottenWRT router: A special VPN box for bad networks run by nazi sysadmins. It already received an internal sound card extension
  • I also have a couple of things to do at home, like finishing the network wiring, pulling a 12V central power supply, install the electricity and plumbing for a dishwasher, doing the schematics of my electric installation, a bit of cleanup and getting rid of old things.
  • Do something of the video rushes i have sitting on my disk
  • Clean up the photo gallery: it’s getting messy
  • Parallel port universal interface: I stopped working on it when BIFFF started.
  • Some hackerspace projects, like the door lock and a relay board.
  • ??? :-)
Will the winter be long enough ?? :-)

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Today in the physical mail box

Thursday, July 14th, 2011
Package content

Package content

Today i received the GSM shield for Arduino from Open Electronics. I rushed to get a pre-paid SIM card to start playing with the new toy.

I just realised that i don’t have an arduino board yet in my personal toolbox, but i can borrow one from the hackerspace to start experimenting.

I have two projects in mind:

  • mailbox watcher: Since the mailbox is far from my apartment and not within my regular walking path, (and i am a lazy person ;-) ), i want the board to send me an SMS when a letter is landing in the mailbox. This is also a nice opportunity to experiment aggressive power saving and see how long can a set of fresh batteries last.
  • Hackerspace door opener: I am also building a motorized lock for the local hackerspace. I don’t know yet what kind of remote control we can use, but it has to be democratic enough. This is not the most original project: the Ghent hackerspace already did it.

Assembly

GSM shield assembled

GSM shield assembled

The shield come as a kit, some soldering is required, but nothing too serious (only through hole components, 2,54 mm pin spacing). In my case, only the switch SW1 was tricky to install.

That’s all for the moment, time to write code.

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Possible backscatter spam coming from my server

Monday, May 30th, 2011

Between 20:00 and 23:00 CET, some backscatter spam slipped through my server due to a misconfiguration on my side.

I was trying to set up a secondary MX for the non-profit association BxLUG,an association promoting Free Software in Brussels.

The configuration files have been reverted to their original versions. It might take some time for the DNS entries to propagate.

I am sorry for any inconvenience it might have caused. In the meantime, i have some reading to do…

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EPIC FAIL

Thursday, May 12th, 2011

Ce matin, à vélo, sur le chemin du travail (et pas loin de l’arrivée en plus).

This morning, on the bicycle, on the way to work (and very close to my destination).

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Opening the Vasco Digipass 810

Thursday, February 24th, 2011
Vasco Digipass 810

Vasco Digipass 810

Many belgian and european banks are providing their customers with a device that look like a small calculator. This device, coupled with your bank card,  is used to secure and authenticate the transactions when using internet banking.

Since that device is fairly standard, there is nothing stopping you from using the reader from bank A with your card from bank Z and vice versa, because the crypto processing is happening on the chip of your card.

Knowing that the heavy crypto work is delegated to the bank card, it is safe to assume that the device is quite dumb: a keypad to feed data to the card, a screen to display the results and a micro-controller to do some simple housekeeping tasks, like update the screen, poll the keypad, clock the card and send/receive data.

I have no proof of what’s described above, but since mine had dead batteries after five years of use, it has become a prime candidate for exploration, so let’s open the case !! :-)

Ugh !!

Digipass cracked open

Opened !!

It was a tough nut to crack !!

There are no screws and no clips holding it closed: the two halves of the case are welded together !! This is another prime example of planned obsolescence and wasteful engineering. There is no way to open it cleanly, you need to break it apart as careful as possible to get access to the main PCB and the batteries. Your ability to close the box afterward will fully depend on how you open it in the first place.

The batteries are nothing exotic: just two CR-2032 button cells. They are wired in series on the PCB, because many smartcards require a 5V power supply to work properly.

Circuit board detail

All test pads are clearly labelled !

When you observe the PCB, there are a lot of interesting test points, all properly labeled. A hacker’s dream. :-)

Fried !!

Unfortunately, while groping at it with a multimeter set to continuity tester, i fried the microcontroller. Apparently, that kind of invasive measurement was enough to kill it.

I wanted to check the continuity between the SDATA test pad and the DATA line on the card connector, the SCLK and the CLOCK line of the card connector. There was no continuity between those points and the J2 pad is still a mystery of what the purpose could be. An optional eeprom maybe ?

I received a new reader to continue with my day to day banking operations, but i still want to see the data flowing between the card and the reader. My mistake is just a setback: i will change strategy and try to (ab)use the reader as-is, without opening the case. :-)

More to come later. In the meantime, here are the Manufacturer’s information

 

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IPv6 mining exploitation (digging tunnels)

Tuesday, November 23rd, 2010

IPv6 in IPv4

This is the most common situation: you want your IPv6 connectivity on your road warrior through your VPN:

Debian/Ubuntu:

router: /etc/network/interfaces

auto tunv6
iface tunv6 inet6 v4tunnel
address 2001:cafe:babe:1::1
netmask 64
endpoint 192.168.255.10
local 192.168.255.1
ttl 64

road warrior: /etc/network/interfaces

auto tunv6
iface tunv6 inet6 v4tunnel
address 2001:cafe:babe:1::2
netmask 64
gateway 2001:cafe:babe:1::1
endpoint 192.168.255.1
local 192.168.255.10
ttl 64

Shell commands:

Machine A:

ip tunnel add v6tun mode sit remote 192.168.255.10 local 192.168.255.1 ttl 63
ip link set v6tun up mtu 1280
ip addr add 2001:cafe:babe:1::1/96 dev v6tun

Machine B:

ip tunnel add v6tun mode sit remote 192.168.255.1 local 192.168.255.10 ttl 63
ip link set v6tun up mtu 1280
ip addr add 2001:cafe:babe:1::2/96 dev v6tun

IPv4 in IPv6

The weirdest and most interesting one: suppose you have equipment that is not IPv6 compatible, yet you want to connect them through a v6-only link between the two endpoints

Machine A:

ip -6 tunnel add v4tun mode ipip6 local 2a00:ffde:4567:edde::4987 remote 2001:473:fece:cafe::5179
ip addr add 192.168.99.1/24 dev v4tun
ip link set dev v4tun up

Machine B:

ip -6 tunnel add v4tun mode ipip6 remote 2a00:ffde:4567:edde::4987 local 2001:473:fece:cafe::5179
ip addr add 192.168.99.2/24 dev v4tun
ip link set dev v4tun up

Sources:

http://linux-hacks.blogspot.com/2008/02/howto-ipv6-ipv6-tunnel-and-ip4-ipv6.html

(Work in progress: this page will be syncronized with this one)

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Acer Aspire One review: two years later

Sunday, June 27th, 2010

Two years ago i bought my first netbook: here are my impressions

Acer Aspire One

The good

  • The laptop is very light and pleasant to carry around
  • It came with Linpus Linux pre-installed. This mean i didn’t have to pay the Microsoft tax. Since i’m running Debian on it, that install was quickly ditched.
  • There is a gap between the screen and the main chassis, allowing me to hold it open and straight with one hand. There was a note in the user manual that this is NOT the way to hold it (risk of crushed fingers) This is really a killer feature for a road warrior that should be more developped.

The bad

  • small screen, low resolution. This cause a problem with many applications where some dialog boxes “sink” under the bottom of the screen.
  • battery life: i have about two hours of usable battery life: this can be tight sometimes
  • Lack of 3G modem: That was not an issue during the first five months because i didn’t have a subscription at the time. Now i have one and i’m stuck with that huge USB modem hanging from the USB port. A small extension cord and some velcro adhesive partially solved the bulky adapter problem. I’m now trying to find 90° angled male USB A connector to keep the size under control.
  • No bluetooth. Not really an issue because there are USB adapters on the market that stick out by less than 5 mm. Less opportunities to cause damage.
  • Limited CPU ressources: The machine has a hard time to keep up with heavy applications like playing a flash video or running the compiler. You just need to be very patient on that.

The ugly

  • After eight months of use, the right touchpad button was not working anymore.
  • It failed totally ten months after purchase: when turned on, the fan and harddisk were spinning, but the screen stayed black (no backlight) and there was no activity. This was fixed under warranty. However, i had to fight to get it fixed: the first time i got it back, the problem was still there. And the reseller told me that they changed the motherboard. It then went back for repair and it was fixed one month later. In total, i have been without for two months
  • To access the harddisk, you have to COMPLETELY DISMANTLE the laptop. That was a real PITA.

Conclusion

Despite it’s flaws, this machine has become my main workhorse when i’m away from home and saved my butt a few times already. After two years of daily carrying and nearly daily use, there are no cracks in the shell. My previous laptops failed by the case, with cracks at very nasty places after about two years of moderate use and carrying. I don’t plan to retire it at the moment: i tend to keep my machines until they are horribly obsolete or simply fall apart. Let’s see in about two years then. :-)

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